Support is requested to permit continued participation in clinical and laboratory investigative activities in the Southwest Oncology Group. Specifically these funds will assist in support of our effort in cooperative cancer therapy trials which utilize a combination of surgery, and/or radiation therapy, and/or chemotherapy for the investigative clinical trials of leukemias, lymphomas, and a variety of childhood solid tumors. Emphasis will be placed on integrated multi-modality treatment programs in Phase III randomized prospective studies. We are also participating in several pilot studies of new drug treatment programs, in Phase II trials, and non-randomized studies. Additionally, continued support for immunologic evaluation of all new acute lymphocytic leukemia patients in the pediatric division of SWOG is requested. Specifically cytoplasmic staining (characteristic of pr-B cells) of lymphoblasts prepared on slides and shipped to us is being accomplished efficiently as an ongoing groupwide project, in order to better characterize and classify lymphoid malignancies. Support is also requested for two new projects. The first will examine the role of HLA typing (especially B lymphocyte antigen typing) in predicting risk for or resistance to malignancy and also relationships to survival duration once malignancy is established. A second project will establish the incidence of circulating immune complexes in neuroblastoma, acute lymphoblastic leukemia, and osteogenic sarcoma and their correlation with disease activity.